Practical 3 Phagocytosis

Phagocytosis– Lymphocytes (~ 30%)
– Granulocytes (~ 70%)
– Eosinophils (~ 3%)
Non-professional Phagocytes
Blood, lymph and lymph nodes Lymphocytes
Skin Epithelial cells
Connective tissue Fibroblasts
Blood neutrophils, monocytes
Gut and intestinal Peyer's patches macrophages
Skin
Fagocytosis Phagocytosis and Bacterial Pathogens
1.Phagocytosis is a component of innate and aquired immunity. It is the principal
means of destroying pathogenic bacteria and fungi. Phagocytosis initiates the
process of antigen presentation.
2.Many phagocytic receptors recognize a diverse array of microbial pathogens.
Some pathogens (e.g., S. pneumoniae) require opsonization for their clearance.
3.Bugs fight back.
remodeling. Ingestion of apoptotic bodies is immunologically “silent” and is
normally accompanied by a suppression of inflammation.
5.Failure of this mechanism may result in autoimmunity.
Inhibit adherence: M protein,
Lyse phagocytes: Membrane
Microbial Evasion of Phagocytosis
Fagocytosis, activity and index. • The phagocytosis test allows the quantitative determination of leukocyte phagocytosis
(ingestion of bacteria or yests). In the phagocytosis test whole blood is incubated with E. coli or Candida sp. The blood smear is done and stained by May Grunwald method.
• It measures: • - the percentage of neutrophils that have ingested bacteria – PHAGOCYTIC • ACTIVITY
• - number of ingested bacteria per one phagocytic cell- it reflects functional • properties of phagocytes - PHAGOCYTIC INDEX
• phagocyting PMN´s and non-phagocyting PMN´s untill 100. • Number of phagocyting PMNL in % is determining the phagocytosis or phagocytic activity.
• In phagocyting PMNL we register the number of foreign bodies – yeast that are localised
intracellularly. • The fagocytosis index is calculated by dividin the no of phagocyted foreign bodies by no of
phagocyting PMNL. This is the value of functional properties of phagocytes.
Phagocytosis of candida albicans by human nuetrophils
Phagocytosis – FA- activity, FI - index
FA % = of phagocyting PMN´s
• phagocyting PMN´s and non-phagocyting PMN´s untill 100.
• Number of phagocyting PMNL in % is determining the phagocytosis or phagocytic activity.
FA = 77,1 +- 8,8 %
-------------------------------------------------------------------- The fagocytosis index is calculated by dividin the of phagocyted foreign bodies by of
phagocyting PMNL. This is the value of functional properties of phagocytes.
of fagocyted yeasts
FI = 3,6 +- 0,8